Lennox Lewis retained his heavyweight crown after the referee stopped his fight against Vitali Klitschko at the end of the sixth round in Los Angeles.

The Brit took the fight in controversial fashion with the Ukrainian definitely upset at the decision in the Staples Centre.

Lewis retained his World Boxing Council crown after opening up two huge cuts above and below Klitschko's left eye.

Referee Lou Moret acted on Dr Paul Wallace's advice to stop the fight because of the severe injuries to the Californian-based fighter's face.

Klitschko paraded around the ring afterwards insisting he should have been allowed to continue and swung a couple of punches at Lewis as officials crowded round.

The decision was greeted with boos from many in the around 10,000 crowd at the arena.

But the decision gave Lewis his 15th victory in the 19th title bout of his career.

The Londoner can now face former middleweight champion Roy Jones Jnr in a money-spinning final pay-day before hanging up his gloves after a 14-year professional career.

Lewis had hinted before this fight - the heaviest heavyweight contest in history - that he would quit the ring after facing Jones.

The fight was stopped with Klitschko ahead by two points on all three judges' scorecards.

Lewis had looked in trouble as Klitschko clearly won the first two rounds.

The 37-year-old's sluggish opening raised fears he had not taken the fight seriously, as he did when he suffered his shock defeat to Hasim Rahman in South Africa just over two years ago.

But Lewis, half a stone heavier than when he demolished Mike Tyson in Memphis just over a year ago, responded like a champion in the third round.

Klitschko was left with blood pouring from a cut above his left eye as he was repeatedly caught by Lewis.

But Klitschko refused to buckle and took the next two rounds on the decision of two of the judges despite the cut again opening up.

Lewis opened up a cut below the eye in round six and this was enough to give him the disputed victory.

The referee stopped the fight just before the bell for the seventh round with the doctor saying that Klitschko could not see out of his left eye.

Klitschko was immediately out of his stool and was furious at the decision. There was nothing he could do.

Long after Lewis had left the ring to boos Klitschko was wandering round with arms aloft as in victory.

Lewis had come into the fight weighing his heaviest ever at 18st 4lb.

He felt Klitschko was lucky the fight was stopped as it saved the challenger from further punishment.

"There's no way he could have finished the fight," Lewis told Sky Box Office.

"If you look at the state of his face, there is no way. He is lucky the fight was stopped."

He insisted Klitschko had not proved a tougher challenger than he had expected.

"No, not really. Of course he can compete with me, that's why he is in the number one position.

"He would have got knocked out in the next couple of rounds. He was definitely deteriorating.

"I do give him credit. He has an unusual European style, plus I only had a week to prepare for it."

A big right hand opened the cut above Klitschko's left eye and led to the stoppage, and Lewis denied Klitschko had successfully avoided his big right hand.

"I wouldn't say he avoided them. The next couple of rounds would have told you the whole thing."

Lewis looked tired, but said: "I was just getting my second wind."

He conceded he was rocked by Klitschko in the second round, and added: "It definitely did wake me up. We're big guys, so any punch from both of us is going to hurt. I hurt him a couple of time - more times than he hurt me.

"I still feel he cannot go the distance with me. As you could see he was definitely deteriorating.

"I wanted it to be a dogfight, because I know when the going gets tough, the tough get going, and I am tougher than him."

Lewis feels Klitschko may have a case for a money-spinning rematch, and asked if the Ukrainian would get a second chance, said: "If it calls for it and the money is right, then yeah, definitely."

Dr Wallace believed he had to stop the fight because Klitschko was unable to defend himself.

He said: "He (Klitschko) had to move his head to see me. At that point I had no other option than to stop the fight.

"If he had to move his head to see me, there was no way he could defend himself."

However, Klitschko could not understand the decision to stop the fight, and claimed he would have won had the referee not intervened.

"Lennox Lewis does not have good condition, he is very heavy," Klitschko told Sky Box Office. "It was my strategy to make him tired.

"I see very well. I don't know why the doctor stopped the fight. I feel very well. I know I can fight.

"I know if this fight had gone on I would win. I would win the fight by points."

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